The article discusses various causes of floor damage in the sacred building. The results of observations and tests have been presented. The main reason for the cracking of the floor is uneven settlement of the ground. Originally, the cause of uneven settlement in soil contraction (clayey soil) was sought for. Recent studies, however, suggest that the main cause is probably poor soil compaction. Attention was drawn to the necessity of further damage monitoring in order to confirm this assumption. The temporary floor repair methods are suggested.

Keywords: sacred building; damage; concrete ground floor.